It has been conventional in the clothing industry to cut clothing pieces from layers of fabric called lays. These lays of material can be as much as 4 to 6 inches thick, 5 feet wide and 10 to 15 yards long. The individual fabric pieces are cut using a paper marker sheet which is placed on the lay of material as a guide. The marker sheet contains replicas of the clothing patterns arranged in closely spaced relation to one another to provide the maximum utilization of the cloth to be cut.
Marker sheets have conventionally been made by positioning paperboard patterns on a light table within markings on the table showing the dimensions of the lay of fabric. The paperboard pattern pieces were arranged in closely spaced relation to each other to minimize waste in the fabric to be cut. After the paperboard patterns were arranged in the desired layout, they were covered with a sheet of clear heavy plastic to hold them in place. A sheet of light sensitive paper of the diazotype has then spread over the plastic sheet. The patterns and diazopaper were exposed to light. The diazopaper was then developed by an ammonia process to make a permanent master copy from which duplicate marker sheets were made.
In cutting plaid fabrics or fabrics having repeating designs, it is necessary to cut the fabric larger than the pattern to allow for alignment of the plaid or design before a final cut of the fabric is made. The fabric is cut oversize on one or more sides of the pattern depending on whether or not the plaid or design repeats in one or both directions. Thus, when making marker sheets for fabrics of this type, it is necessary to make the markers oversize. This is presently accomplished by positioning the paperboard patterns on the light table so that there is sufficient spacing between the patterns to provide the extra material. This additional space is called "blocking". When the patterns are properly laid out on the light table, a diazopaper master copy is made of the pattern layout in the manner previously described. Copies are then made from the master. The blocking distances around the pattern marker must be drawn in on the marker sheet copy. This manual marking of blocking distances must be done on each copy since each copy is destroyed when it is used.
The foregoing processes are time consuming and, since marker makers are among the most highly paid workers in the clothing industry, this process is extremely expensive. Additionally, the clothing manufacturers must purchase and store large numbers of paperboard patterns. These patterns are not only expensive but also require large amount of storage space. For these reasons, many attempts have been made to eliminate or modify the conventional methods of making marker sheets for cutting both ordinary and plaid fabrics. For example, U.S. Pat. No. 3,816,924 to Frank J. Cutri teaches the use of thin flexible self-supporting plastic sheets having opaque markings thereon which are tracings of the pattern to be cut. Markings also record other information such as notch markings, drill holes, sizes and other cutting instructions. This patent calls for the cutting of the thin sheet of plastic to a configuration slightly larger than and approximately conforming to the configuration of the pattern. The pattern is then traced onto the transparent plastic sheet using the opaque material. In another aspect, the Cutri patent teaches the cutting of a plastic pattern having the same outline as a paperboard pattern piece and the use of the plastic pattern to trace the outline of the pattern.
The clothing industry has also attempted to overcome the difficulties and to reduce the expense of the conventional marker making processes in other ways. One method has been through the use of miniature patterns. Miniature patterns are laid out on a replica of a marker sheet constructed to the same scale. The miniature patterns are arranged on the miniature marker sheet to minimize waste of the cloth to be cut. It has been found to be more efficient to make a layout using miniature patterns since the person arranging the miniature patterns has a better overall view of the marker sheet and the relationship between the various patterns then he would have using full size patterns and a full size marker sheet. The advantages of working with miniatures can be better appreciated when it is realized that a full size layout of patterns can cover an area as large as 5 feet by 50 to 75 feet. When the miniature patterns are laid out in the desired manner on the miniature replica of the marker sheet, a photograph can be made of the layout. This photograph can be used by a marker maker as a guide to lay out the full size patterns on a full size marker sheet.
Miniature pattern layouts on miniature replicas of marker sheets have also been used to make full size marker sheets. This has been accomplished by making a contact print of the miniature marker layout on a negative film. The negative film is enlarged in a continuous enlarger which projects and prints the pattern layout on a full size light sensitive marker paper. However, the manufacture of full size marker sheets from miniature patterns in this continous enlargement process has not been entirely satisfactory. It is believed that the problem resides in the miniature patterns. Conventionally, the miniature patterns have been cut from a thin sheet of plastic using a pantograph device which follows the outline of a full size paperboard pattern. The miniature plastic pattern is cut by a heated stylus carried by the pantograph. The quality of the edges of the miniature pattern depends on the skill of the pantograph operator. If the movement of the stylus is not consistently uniform, the miniature pattern will not be an exact reduced scale replica of the full size pattern. Also, the use of a heated stylus can form ragged edges on the miniature pattern as well as burn and melt spots when the stylus is moved at an irregular or too slow a rate. Imperfections in the edges of the miniature patterns are magnified when the patterns are enlarged and printed on the full size marker sheet.